Boulder Vermicomposting

Redworm composting…in a 2L bottle

Ran across an interesting book called Bottle Biology (apparently funded by the NSF).

Google books has a preview online, and there are two pages devoted to creating a worm bin in a 2L plastic bottle.  They tell you just enough to whet your appetite, though:

Worms play a major role in breaking down plant matter and creating fertile soil.  Earthworms eat fallen leaves and other plant parts.  Their droppings, or “castings,” fertilize the soil. … Observe wonderful worm activity yourself by building a worm column.

Add comment January 3rd, 2010

Holiday worms?

This article, from Boulder Organic, mentions giving worms for the holidays:

Downing says ellie’s also carries worm-composting bins that are about 14 inches square and two feet high. They range from $75 to $85.

The worms must be purchased separately, she says, but you can complement the gift with a copy of the book Worms Eat My Garbage by Mary Appelhof for $12.95.

This seems like an alright idea, but for maximum success of a worm bin, I feel it’d be better to wait until spring to give this gift.  Then it’s more likely to have a happy place in a ‘in-between space’ like a garage or a basement.  Also, one won’t be as tempted to overfeed it, since there’ll be a compost pile for organic waste (or at least, the weather will be better for creating one).

What do you think?

Add comment December 16th, 2009

Myco-vermicomposting article

The Mad Bioneer, over in Arizona, has a fascinating post on combining vermicomposting with mycoculture, or the raising of mushrooms.  I’ve raised mushrooms briefly, but only for food, not for composting purposes.  It looks liek worms and mushrooms complement each other, at least when your primary material is wood chips.  The mushrooms can break down the wood chips, and the worms can eat what’s broken down, as well as the mycelium (mushroom ‘roots’).

He also shares lessons.  He talks about what you can expect in terms of mushroom production:

The worms will reduce the number of mushrooms you get from the wood chips by at least half. I don’t think they can really get into the log to steal from there. They eat the mycelium, weakening the mycelium and reducing its ability to produce mushrooms. So if you are doing it for mushroom production, have more of a two-bin system. Let the mushrooms grow alone on the wood chips first, then let the worms have a crack at it to finish it off. If you try the worms first and then the mycelium, the worms get a lovely snack and you get no mushrooms at all. I tried inoculating a worm bin with some mushroom spawn that I didn’t really have plans for. I came back a few days later to see if it had taken off and it was completely gone. The worms had eaten it.

Watch out for those red wigglers!  They eat everything.

And also about what he thinks the soil nutrition content is for the broken down wood chips (not too balanced):

Lately some of my plants in the compost have been kind of pathetic looking. I think it might be due to the nutrient content of the soil. After all, it was made from pure wood chips. I haven’t had a chance to test the soil, but my guess is that it is a little low in nitrogen at least and possibly potassium and phosphorus. I would recommend the addition of a good organic rock-based fertilizer regularly with the various layers of organic matter that you add. The rock-based fertilizer, such as greensand for potassium and rock phosphate for phosphorus, will have more staying power in the soil than the quick-fix type fertilizers. I don’t know of a rock-based source of nitrogen, so I use blood meal. They will also be good for the mushrooms that you get in there, as they are used to breaking down rock for minerals. A little sand or pea gravel in the layers might also be good to help out the soil structure. Of course, ignore this if you are composting in one place and using the compost elsewhere.

This makes sense.  The redworms can turn nutrients into different, more accessible forms, but, as I mention in my post about sending my worm castings to a soil lab, the chemical contents of your bin depend on what you put into it.   Earthworms aren’t alchemists!

Regardless, this sounds like an adventure in composting.  Definitely read the whole article.  I also enjoyed one of his other articles about mycorrhizal fungus.

Add comment October 26th, 2009

Upcoming composting workshop with John Anderson on Nov 7

From the Broomfield Enterprise:

John “The Worm Man” Anderson, an expert in the art of vermicomposting, will present a workshop on the basics of using worms to compost kitchen and yard waste from 9 to 11 a.m. Saturday, Nov. 7, in the Lakeshore Room of the Broomfield Community Center at 280 Lamar St. Cost: $10. Sponsored by Broomfield master gardeners. Registration required: 720-887-2286.

Here’s all their upcoming events.

Add comment October 19th, 2009

Worm Bin Components: The container

The container of a worm bin, especially a home worm bin, fulfills a couple of needs.

• keeps worms in a habitat that they enjoy: humid and dark
• keeps worms and other bin inhabitants in
• pleasing to the eye
• durable
• cheap
• light, so you can move it if you need to

I’ve used the following containers for worm bins:

• compost bin
• rubbermaid box
• wooden box

Each of these has benefits and drawbacks.

The compost bin is what I currently use.  It is very durable, looks alright, and provides a great environment for the worms.  They especially like the fact that they can get into the ground–giving worms more control over their environment leads to happier worms.  However, the compost bin is not mobile at all.  If I had moles or some other pest, it would not do a great job of preventing that pest from invading the bin (though I did put some chicken wire underneath the bin).  This bin was also about $50, and I got a special deal through the county of Boulder.  So, not all that cheap.

The rubbermaid bin is cheap, durable, and light.  My major issue with it is that I need a lot of rubbermaid bins to process all of my materials.  I’ve read of people stacking bins 4 and 5 high, so if you want some concentrated worm power, this may be a container to use.  Melanie, a longtime vermicomposter, uses a “10 gallon rubbermaid tote”.  And here’s a great pdf from the Boulder Compost Company about making your own worm bin.

The wood box I build was fun.  You can build just the size of worm bin you want (mine was 2ftx2ft), and make it look anyway you want.  If you make it out of scraps, you can’t get cheaper.  However, wood is heavier than plastic and definitely not as durable.  The humidity that red wigglers like causes wood to break down.  I used my bin for a year or two and saw some wear and tear, though it did not fall apart.  I have read that wood bins should be rested every few years to maximize their longevity.

In short, you’re looking for a container that will fit well with your needs.  Just getting into worming?  Consider a cheap plastic tote.  Have a lot of worms–think about a bigger container.  Just keep the criteria at the top of this post in mind, and you’ll do fine.

Add comment October 6th, 2009

Worm Bin Components: Bedding materials

A key component of the redworm bin system is the bedding.  This is the carbon rich environment into which you will place the worms and the food scraps.  (This entire post is probably of interest only to the home worm keeper–industrial worm operations have different needs.)

Bedding materials need to have the following qualities:

• carbon rich; if not, then hot composting and ammoniaifcation can occur
• capable of absorbing water; as the worms like to live in a wet environment
• relatively light; for moving the bin around
• cheap; you’ll go through a lot of bedding

I’ve used the following materials successfully:

• shredded paper and newspaper
• shredded cardboard
• leaves
• paper towels
• yard waste (dried grass clippings, etc)

Each of these has their pluses and minuses, but my current favorite is leaves.  I typically will find 6-10 bags of leaves on the street in the fall.  I gather those up and use them throughout the following summer.  For an indoor bin, shredded paper might be better, as leaves introduce other insects and can mat.

Don’t be shy about adding more bedding.  Redworms (and their attendant microorganisms) will not only eat your food scraps, they’ll also break down the bedding matter.

Add comment September 27th, 2009

How to feed an existing worm bin?

I’m helping a local community garden with their worm bin.  They use it primarily for educational purposes, mostly for children.  Boulder Compost set up the bin a few years back.

I wrote up this how to feed one page pamphlet for them.  I think it’s useful for anyone who inherits a working worm bin, so I’m sharing it here.

Add comment August 28th, 2009

Worm Weight Calculator

I built an online calculator to let you figure out how the weight of worms you have in your bin by separating out just a fraction of them.  It’s the same method I outlined here, when I found that I have approximately 7 lbs of worms in my bin.  But now the calculator does all the work.

Check it out.

Add comment July 28th, 2009

Red wigglers to the rescue

Boulder Organic, a new publication from the folks at the Boulder Weekly, have a new article about red worm composting, John Anderson, and rescuing a bad compost operation.  John is his characteristic, no b.s. self:

“Our prime directive in this culture is to make more food to make more people to sell more shit to,” he says. “The system has to stop designing waste. We design things with waste on purpose because of somebody’s back pocket.”

The article also discusses other important aspects of home wormkeeping, including how to feed and harvest red wigglers, and provides a list of things that can be vermicomposted (one which is slightly different than the one I’ve provided).

Add comment June 22nd, 2009

Interview: Experiments, banned egg shells, trash reduction, and compost benefits

Here’s the second part of my interview with Linda and Mark.  The first part is here.

Linda: The last time everything smelled great by the time we harvested. Actually, most of the time we’ve had the worm box it smelled great, but this time we’ve really been feeding the worms a lot, although I think there starting to catch up.  Actually they’ve eaten quite a bit. And on this side I’m doing an experiment.

Dan: On the new side.

L: I layered shredded newspaper with bark.

D: OK, I see some big chunks of bark.

L: There are big chunks and small chunks.  I read that the chunks can often help provide oxygen and air space.

D: Oh, interesting…What kind of bark is that, just whatever you have laying around?

L: Yes, we heat with firewood a lot.

D: OK, gotcha.

L: So it’s usually leftover; actually we have a whole garbage pail full of it.

D: I see you are putting carpet across the top. Is that insulation and smell control? Or keeping the worms out of the light so you can open the box easier? What’s the point of the carpet?

L: Well, the point of the carpet was that ‘John-the-worm-man’ said that worms absolutely love carpet. And, I will totally agree, they love it. They will come all the way to surface and just hang-out on top when the carpet is there. And I think it helps keep the moisture in. I think it also helps keep the heat in and it’s like them being under a little rock.

D: Is it natural carpet or synthetic?  They’re not going to eat it, right?

Mark: No, they’re not going to eat it.

L: That’s what he had recommended. We just happen to have that synthetic scrap of carpet.

M: And, last Saturday when we had the cool, rainy weather there, when I pulled that up there were worms actually on the back side of the carpet. They had actually come up to the top and they were everywhere, there was almost like a highway; more like a parking lot. It’s kind of interesting to see how the worm’s behavior would change with the weather, and that’s when I got the idea that I should put in the insulated top. I noticed our temperatures did much better.

D: What were they doing before the top was on?

M: Before the top was on it was within 2 or 3 degrees of ambient. With the insulation in there it was a solid ten degree difference, in fact this morning it was 57 and the outside air temperature it was 44. It does make quite a bit of difference if you can believe these little instruments that were using.

D: It’s not scientific precision, but it’s good enough for this kind of experiment.

L: And, definitely, letting it capture some heat during the day.

M: Yesterday, we hit in the 90’s in fact.

L: Just the air [in the bin].

M: I think the soil temperature – you need a soil thermometer, but you’ll find, at least now, it’s cooler, but of course at night time it gives it up, so to speak.

L: So, one thing that we haven’t done, and I wonder if we should do, is that they recommend that holes be drilled all along the edges.

D: On the sides of the edges or the bottom?

M: The bottom is drilled.

D: So, like midway or 2/3 of the way down the sides of the worm box?

L: We don’t have that now, and we can see the worms seem to be multiplying and pretty happy, but I know I’ve read that you should have more holes.

D: Just for oxygenation?

L: I do open it and stir it. I think those worms are doing well.

D: Yea, they look pretty fantastic

L: I can’t believe how much they’ve eaten on this side; this was solid newspaper.

D: Have you guys noticed your trash doesn’t go out as often?  Has it affected your life other than to come and check out the cool worms?

M: Our daughter loves to come and say “see’em, see’em, see’em”, and show her friends. Prior to getting a worm box we were composting. Of course it is a little bit different with that kind of compost. Whereas the first load that that we got in the worm box we put it over there and within a week we noticed almost an immediate effect. Yea, a basil plant that wasn’t that great, it turned into a prize. And then the pile started to attract wildlife.

L: We saw a huge snake wrapped around the pile.

M: It was a 3’ garter snake just sitting in there. The pile is over here and in fact I just poked around in there and found a bunch of baby worms

D: Sure, cocoons that you moved have hatched.

M: Its been out here for about a month… probably a raccoon or something digging around for scraps.  You can see when I dig down, there’s a lot of tiny worms, there just picking up scraps.  The richness of the soil is what really impresses me, because to the layman’s eyes, someone would just look at this and maybe say oh you got some compost or you got some potting soil or something like that.  This was food and newspaper, and now it is this incredibly lush rich looking soil, which looking at the basil and the eggplant it really likes the flavor.

Basil plant near vermicompost

D: So how is that different from the compost that you guys have done in the past, in terms of speed, in terms of quality?

M: I’d say that speed is one. it’s just amazing just how quickly it actually turns it into something that you can use, as opposed to the compost that we did in the past we would say compost for a season, say in the spring, and then the following spring we would take that, depending on how it was broken down, we would move the highest quality portion of it over to our garden.

L: Seems like it would take a year. And now we get the stuff in 3 months

M: And there’s something different about it. I can’t put my finger on it, but it’s different that the compost.

D: I sent in a sample of worm castings to a soil lab and got a bunch of numbers back and it would be very interesting to look and see what compost has for potassium, for all the vital elements that plants need.

M: It would be really fascinating because the results, I mean, this compost ‘rocks’. It’s much better than what we’ve been using before. And, the speed, again, at which the worms work are very impressive and their robust, I mean, the temperature drops down to 40 degrees, its chilly, and how much activity you can see today, they are a happy bunch in there.

D: Sure, they are bouncing back.

M: I kind of wonder what’s going to happen to [the worms outside of the bin] if there just going to burrow in the soil, or is this the end?

L: I think this is the end.

D: My understanding is that the type of worms, the red wigglers, need a lot of organic matter, so if your not providing that for them, maybe if you got straw and whatnot.

M: It was actually pretty neat because when we divided up the bin we actually moved this to one side and we didn’t feed it any more at that time and we just fed the new side. It was amazing. There was always a few stragglers left, and we just tossed them over there [to the new side]. For the most part they all sensed it, or smelled it, or whatever. They bee-lined it to the food. What was left were these little tiny cocoons.

L: I did leave it like that for 2 months, though.

D: 2 months is a long time.

L: And part of it was, I just happened to be gone. I thought about doing it before I left and I just said I will just give it some extra time.

Worm closeup

D: Now, when you moved it to the one side, one of my concerns would be that the side you’re putting food in would get over fed. Is that kind of what happened?

L: No, it didn’t happen. I’m not really sure why. I think there were enough worms to consume what we were putting in.

D: I guess you have a certain amount of worms, roughly, in a smaller space?

L: Yea and I think they are multiplying more now. It has taken awhile.

D: Mark, you said you were surprised by the fertility. Were there any other surprises you guys have had in terms of what works?

L: It’s been fun

M: [Our daughter]  likes it. Its one of those things we like to encourage with her, because she’s getting to see the workings of the earth. And she‘s ecstatic, even more so than Linda and myself. After the worm box was built, Linda was looking at it almost everyday.

D: I certainly did that with my first worm box.

M: But, I think now we’re down to 3 times a week.  We worry about the worms sometimes, like when it gets cold. I went out and bought another temperature transmitter because you put all this attention to them it would be a shame for them to perish.

D: Are you planning to do anything with harvesting the excess worms like giving them to friends.

L: The surprise that I have had is just about every one I have asked has back out.

D: Taking worms from you for free, essentially?

L: Yes, they got scared.

D: Have you asked them what they were scared of?

L: I think it sounded good to begin with, but when reality set in they just weren’t interested. One friend decided they now have the City of Boulder composting, so they preferred to do that. Other people are a little worried that it’s going to take too much work, although I don’t believe it takes work. And I think Sharon and Dave, some friends that were just here, I would suspect that they will do it next year.

I guess the other surprise is I thought that the worms would have multiplied enough by now to eat all of our excess food. It seems like a lot of the worm advertisements show that worms eat about 7 pounds a week.

D: A pound of worms can eat between a half-a-pound to a pound a day

L: So I don’t know how many worms we have but I’m guessing were feeding this about 7 lbs a week and maybe they are eating it.

M: Here you go Dan, just a quick survey [of the contents of the worm bin].

D: Ok, I see some onions, I see bananas, I see, looks like turnip tops. Is that pineapple?

M: That’s spaghetti squash. We usually save the best for the worms.  Maybe just a little bit of caffeine in the form of used coffee grounds, just to keep the guys motivated. Eggshells… we were actually banning eggshells, but now we are starting to put them back in.

D: Why would you ban them?

M: We were banning them because we weren’t consistent in our delivery. We were sometimes throwing in whole shells; other times we were breaking them up, and it was like ‘well were going to put all those items in with the other compost.’

D: Oh, so you’re still maintaining the compost [pile]?

L: It’s not a proper compost pile.  [Looking in the box] I dug down in here the other day and I hadn’t dug down in a long time and I actually felt kind of bad digging down.

D: Cutting [the worms] in half or something?

M: Can you really kill a worm that way?

L: Yes

D: Yeah.

L: I think they are starting to multiply enough. You know if we have another decent month of weather I think we will have enough to eat all our food. We are not really putting that much in there now in the last few weeks.

M: We have been averaging one complete kitchen composter a week for the compost.  It’s a one gallon stainless steel container.  We make donations about twice a week.

D: Then in the winter time you’re just checking on the worms?

M: Yes, that’s the worm check-in schedule.

L: I don’t usually stir them up. Look at that!

D: Wow, what a mass!

M: I kind of like it because Linda is grossed out and amazed at the same time.  They seem to be a happy bunch. The corn husks are pretty tough for them.

L: The ones that are buried, they love that stringy stuff…

D: What’s that called?

M: The hair, almost.

L: Wow, they moved over here

M: Never a dull moment when you’re poking around the worm box.

D: What other things; eggshells you mentioned they like and the cornhusks. Any other foods that they are huge fans of? Looks like the inside of that squash. That’s fresh.

L: That’s very fresh.

Add comment May 22nd, 2009